The primary goals of Project 1 are (1) to recruit a new national probability sample of 2,100 respondents (aged 25-54) as well as a new stratified sample of 500 African Americans from Milwaukee, Wl (also aged 25-54), and (2) carry out the 2nd longitudinal follow-up ofthe existing samples (MIDUS III). All respondents will complete the same set of assessments - a phone interview (or personal interview in Milwaukee) and selfadministered questionnaires - that were obtained at MIDUS II. A key reason for refreshing (augmenting) the MIDUS samples is to allow for investigation of period effects ofthe economic recession by comparing sameaged adults from the MIDUS I (pre-recession) sample assessed in 1995/96 with the refresher (postrecession) sample assessed in 2011/12 on a multitude of indicators of economic adversity, mental and physical health, and psychosocial moderators. The expanded sample sizes will also facilitate cross-project analyses focused on the interplay of sociodemographic, psychosocial, and biological influences on the health of mid- and later-life adults. The second primary objective, that of launching the 3rd wave of assessments on the existing MIDUS samples ( 5,500 respondents), will allow for more precise and reliable estimates of change in key variables as well as strengthen opportunities for testing psychosocial factors (negative and positive) as moderators or mediators of age-related changes in health. Our revision offers extensive evidence of the many lines of research that have been pursued with MIDUS survey data (255 publications to date, 59 of which are based on MIDUS II data), all of which will be advanced by the planned expansion of the sample and its related focus on the economic recession as well as by carrying out the next longitudinal follow-up of the existing sample. Project 1 also serves as the hub from which all other projects emanate, making its sample recruitment and data collection essential for moving forward all components ofthe MIDUS enterprise. Overall, our planned additions will allow MIDUS to become a major forum for investigating how the economic recession is affecting the health of young and midlife adults, while also move forward the next phase of assessments 9-10 years later (adhering to the interval between MIDUS I and MIDUS II) with the existing sample. In the longer term, our proposed plans lay the groundwork for longitudinal tracking of parallel samples of adults (aged 25-54) from different birth cohorts whose biopsychosocial aging is unfolding in the context of major economic upheaval - hence, our emphasis, akin to Elder's classic work, on adults of the great recession.